1. Field of the Invention
The present invention generally relates to devices for occluding a body lumen, and more specifically relates to a permanent contraceptive or sterilization device for occluding a reproductive tract or lumen. Even more particularly, the present invention relates to a device which causes sterility in women by occluding the female reproductive fallopian tubes using RF (radio frequency) energy.
2. Description of the Prior Art
Many methods of female sterilization have been investigated. One method is surgical tubal ligation, which is a procedure in which the uterine tubules are tied and cut or clamped through an incision made through the wall of the abdomen. Tubal ligation done with a laparotomy requires a surgical incision in the abdomen under general anesthesia. Drawbacks of this procedure necessarily include the risks inherent with anesthesia and the permanent scar formation at the site of the incision. Another technique involves transcervically instilling the sclerosing agent quinacrine into the uterus and fallopian tubes to create a permanent closure of the fallopian tubes. Drawbacks of this procedure include the need of repeat applications and a significant level of side effects.
A further procedure involves transcervically injecting a curable elastomeric composition such as silicone into the fallopian tubes in an amount sufficient to fill the portion of the fallopian tube adjacent the uterus, which composition is allowed to cure and solidify to non-surgically block the tube. This technique is time consuming and requires a high level of technical skill and had poor results with sterilization.
There are also permanent contraceptive or sterilization devices which are transcervically delivered and mechanically anchored within the fallopian tubes and which promote tissue ingrowth into the device and scar tissue formation which eventually may totally occlude each fallopian tube. Such a device is disclosed in U.S. Pat. No. 6,432,116 (Callister et al.) and published U.S. patent application Ser. No. 09/912,067 (Nikolchev et al.).
Sterilization has also been performed using RF (radio frequency) energy. As disclosed in U.S. Pat. No. 5,556,396 (Cohen et al.), an electrically energizable electrode is advanced into the fallopian tube and energized to thermally damage the fallopian tube, thereby causing enough scarring of the fallopian tube to permanent occlude it. Further sterilization devices using RF energy are disclosed in U.S. Pat. No. 6,066,139 (Ryan et al.) and U.S. Pat. No. 6,346,102 (Harrington et al.).